Author Topic: Titanium bolts? Mad waste of money or any purpose?  (Read 9153 times)

Pavel

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Re: Titanium bolts? Mad waste of money or any purpose?
« Reply #15 on: January 06, 2018, 06:01:42 pm »
Mickeg ... how do you find the Titanium frame compared to a steel frame?  It certainly looks good unpainted and from what I've read the ride is supposed to be comfortable. Is there a list of pro's and cons you'd share with us, in the titanium vs steel choice?

mickeg

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Re: Titanium bolts? Mad waste of money or any purpose?
« Reply #16 on: January 07, 2018, 05:26:25 pm »
It really depends on how it is constructed.  The bike in the photo is a touring bike, it is intended to be ridden with a load of camping gear.  But the frame was still quite light, the frame without fork is lighter than my rear wheel with tire (XT M756A hub, 36 Wheelsmith DB-14 spokes, Velocity Dyad rim, Hutchinson Globetrotter 37mm wide 700c tire).  But regarding weight, it still is a touring bike and it weighs a bit over 15 kg.  I suspect that the Titanium cut maybe a kg of weight compared to a steel bike.  I have a steel fork on it, the manufacturer of the frame does not make Titanium forks.  For touring I did not want a Carbon fork.

I was not specifically planning on building up a Titanium bike, but I got lucky and got that frame new for less than half of the manufacturers list price.  I had a bunch of parts that were looking for a new home (new frame) so I was just watching for something in 700c that looked interesting.  I bid on that (on Ebay) and won the auction.  It is not used, I still have manufacturers warranty.

I suspect many of you know how that goes, you suddenly have a higher end new frame that you were going to put a bunch of old parts on.  Suddenly those old parts did not look so good anymore, suddenly new parts looked a lot better.  So, it became a more expensive project than I planned, but I am still quite happy I built it up.  I think my total cost for the bike when I factor in the cost of the parts that I already had to put on it was about the same as the manufacturers list price for just the frame without fork.  And I put an SP dynohub and Luxos U on it, so I did not scrimp on parts.

How does it handle?  Handles like a touring bike, it has very large diameter headtube and downtube for stiffness, these tubes are fatter than on my Nomad.  Rear stays are also pretty big, but they are round and untapered, unlike the tapered and shaped stays on my Nomad.  But if is not as hard a ride as I suspect an Aluminum bike would ride.  And with 37mm wide tires, it is not going to have that hard ride that you would get from high pressure skinny tires.

I have read that Titanium is roughly in between steel and Aluminum for ride characteristics, I would not disagree with that.

Because of the high cost for Titanium bikes, the vast majority of them have high end components, skinny tires, and are built for speed.  There also are a number of mountain bikes made from Titanium, these are often more performance oriented.  I do not expect to see a lot of Titanium bikes being built for touring for that reason, as it does not make much financial sense to put 20 kg of camping gear on an expensive bike that would have been a lot more affordable if it weighed one kg more like a steel bike would have.

So, for touring I have the following:

 - Thorn Nomad for heavy touring, also has S&S couplers to make shipping by airplane less costly if I am willing to take the time to pack and later reassemble it.

 - Thorn Sherpa for medium duty touring, fitted with eight speed cassette (Sram 11/32), bar ends and a triple with half step plus granny (46/42/24), have used this on several tours and I like it for that purpose.

 - The Titanium bike I expect to use more for on-pavement only (on-tarmac only) type of touring with lighter weight loads.  It has the same drivetrain as the Sherpa (eight speed, bar ends and triple with the same exact gearing).  But the final drive ratios are slightly higher with the larger diameter 700c wheel.  I did a five day tour with four panniers and handlebar bag on it, was very happy with it.

I also have an Airnimal Joey (folding bike with 24 inch wheels) that I might try to tour on some day, but have not found a reason to do that yet.

I think most of the historical experience that riders describe about Titanium is based on racing bikes.  Titanium was the thing to have before Carbon became big.  I do not know if it is true, but I have heard that (the now disgraced) Lance Armstrong during his first year of Trek sponsorship insisted on riding on a Titanium bike of a different manufacturer, thus they repainted that other bike to match the Treks and let him race that Titanium bike, but after that first year he conformed and rode Treks.

I am not concerned about corrosion, those of you near salt air might be more concerned.  Titanium has great corrosion resistance.  But I put a coating of frame saver inside my Nomad frame before I built that up to protect the steel.  Such protection on a Titanium frame is unnecessary.

I suspect some of you were puzzled by the odd looking disc mount.  That manufacturer makes both a post mount (as pictured) and a flat mount for the newer flat mount disc brakes, either mount can be fitted to the rear chainstay with three bolts.  This was my first disc brake bike.  I had a non-disk fork that I wanted to use to cut costs, that fork was for rim brakes.  Thus, the bike is rim brake on front wheel and disc on rear.  That mix works quite well, I think my rim brakes (with Koolstop Salmon pads) outperform the disc.

I think I covered all the topics, let me know if you have specific questions.  But, bear in mind that the forum is hosted by a steel frame bike manufacturer, so if you have specific questions, lets handle those by private message.

Pavel

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Re: Titanium bolts? Mad waste of money or any purpose?
« Reply #17 on: January 07, 2018, 07:50:28 pm »
Great write-up.  Thanks.  You are right that saving a kilo makes much less sense on a touring bike, especially for someone such as myself, where comfort, especially for sleep, is the top priority over weight and reliability/simplicity is next.  Still, it sure is a nice looking bike, judging by that one photo.  I'm surprised to hear you tell that the tubes are fatter than on the Thorn. 

PH

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Re: Titanium bolts? Mad waste of money or any purpose?
« Reply #18 on: January 09, 2018, 03:52:34 pm »
I'm surprised to hear you tell that the tubes are fatter than on the Thorn.
You might find this interesting
https://www.ibiscycles.com/support/technical_articles/metallurgy_for_cyclists/the_titanium_advantage/

Steel is heavier but stiffer, tubes of the same dimension would be half the weight but impractically flexible, as the above article says
Quote
steel and titanium are roughly comparable when it comes to the stiffness-to-weight ratio
I'm a bit sceptical that mickeg frame saves a kg, IMO that won't be the case if it's a like for like comparison.
I've just replaced a Ti frame (With a failed weld) with a Mercury, they're no identical but pretty similar, the Merc frame is 190g heavier (Though I've reclaimed that with a lighter EBB and fork)
Photo
https://www.flickr.com/photos/phbike/5592766517/in/album-72157626312048871/

PH

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Re: Titanium bolts? Mad waste of money or any purpose?
« Reply #19 on: January 09, 2018, 03:56:06 pm »
Quote
I can’t work out where there would be 50 bolts (Which by the way will almost definitely be screws)
Well, let's see...

On my Nomad (for example):
....snip....
Total on frame/fork: 37 unless I've lost count
Total on components: 18 22
Grand total: 55 59

All the best,

Dan.
I hadn't taken into account changing the bolts on components, simply because it isn't something I'd do, I'd assume fittings for the likes of stems and brakes had been tested as part of the overall component and would have to be sure of what I was doing before replacing.

PH

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Re: Titanium bolts? Mad waste of money or any purpose?
« Reply #20 on: January 09, 2018, 04:05:28 pm »
And please will people stop calling screws bolts
https://mechanical-engg.com/blogs/entry/534-difference-between-boltscrew-and-stud/

If you're bolting stuff together it'll require a nut on the other side, if you're screwing it together it is, not surprisingly, a screw ;)
You can of course sometimes use one for the other, but it's usually best to use the fastener intended for the purpose.

Andre Jute

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Re: Titanium bolts? Mad waste of money or any purpose?
« Reply #21 on: January 10, 2018, 02:00:35 am »
I hadn't taken into account changing the bolts on components, simply because it isn't something I'd do, I'd assume fittings for the likes of stems and brakes had been tested as part of the overall component and would have to be sure of what I was doing before replacing.

And, for the same reason, if you're replacing a bolt or a screw with a damaged head or for any other reason, don't just replace it with something from your local hardware store of the same size and thread: get the real thing from the OEM (original equipment manufacturer) or his authorized agent, and if you can't, on any critical component (steering, brakes, seat post collar, around the pedals) replace the whole component because it will come with new screws/bolts/studs of the correct tensile rating. Not all threaded items were created equal! And that also gives you a hint to why you shouldn't willy-nilly fit fasteners of different materials to those originally specified to critical components unless, of course, you're a materials engineer who sleeps with Timoshenko under his pillow. Note that there can be situations where a nominally higher spec of fastener can be undesirable, for instance where the native "stretch" in a material has been calculated into the operation of the component, or where part of a component is expected to be removed and refitted multiple times in normal service, in which case steel is hard to beat.

On the other hand, many OEMs sell aftermarket sets of correctly specified stainless screw sets for those who must have the bling. If nylock nuts are included buy spares of these -- yep, you got it, not supposed to be reused. A way round the nylock nut waste is to get two half-nuts for each threaded fastener, torque the first one up to spec, and lock the second one against the first by friction. Works a treat and isn't wasteful.
« Last Edit: January 10, 2018, 11:13:51 pm by Andre Jute »

Danneaux

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Re: Titanium bolts? Mad waste of money or any purpose?
« Reply #22 on: January 10, 2018, 04:32:12 pm »
Jan Heine has posted a cogent piece on the uses of titanium on bikes, weight savings, and design appropriateness here:
https://janheine.wordpress.com/2018/01/09/myth-2-titanium-is-lighter-than-steel/

Best,

Dan.

John Saxby

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Re: Titanium bolts? Mad waste of money or any purpose?
« Reply #23 on: January 10, 2018, 05:40:00 pm »
Thaqnks for that link, Dan. I find Jan heine's blog to be useful on all sorts of issues, and generally well-written.

My own experience with titanium is limited to the past few years, and is varied, but not expensive:

     > I have a couple of ti implants in my lower left jaw, adorned with two trick ceramic crowns. These are about 8 years old now. They replace teeth lost to inadequate dental care a half-century or so ago. Everything seems fine, and half the cost was tax-deductible :)  No reason not to use ti in that setting, so far as I can tell. Its non-oxidizing properties seem very appropriate.

     > My experience with my ti frame on my light-touring Eclipse has been mixed. The frame is well made and nicely finished, and of course shows no signs of rust :) Dimensionally, it fits me well. The bike is about 2 kgs lighter than my Raven, when both have similar specs for fenders, etc., though the Raven has slightly wider rims & tires. The feel of the two bikes is quite different, the Eclipse being much nippier, but the lighter weight of the Eclipse makes little appreciable difference its its speed over the road when I'm riding, because so many other factors are at play. Notably, the Raven fits me much better, as a result of various tweaks I've made to its spec, drawing on a decade of experience with the Eclipse. The better fit makes the Raven both more comfortable and thus (I think) more efficient.

     > The matter of utility of the two bikes is affected by other considerations, too. My Eclipse originally came with carbon forks, which had no provision for fenders, nor for a front rack. I used clip-on fenders, which were OK but no more than that, and I used a front rack fixed at the bolt bosses and the skewer. I refreshed the bike a couple of springs ago, replacing the CF forks with a nice Surly steel fork, and that's been brilliant: dead steady on fast downhills, with nice fitting for a smart VO alloy fender and a light rack, if I wanted to fit one.

     > And, of course, the Raven has a Rohloff, while the Eclipse is a derailleur bike. I had a decade of headaches with the drivetrains on the Eclipse, which we don't need to dwell on here because it is a Bad Vibe for me.

Conclusion:  The Eclipse is a nice bike for rides of a few hours or less, and looks very spiffy indeed.  I'm not taking it to 'Straya next week, however, because (i) the airborne sand on Gold Coast roads wrecks chains and cogsets, and the Raven has a 'glider; (ii) the Raven's gearing will let me spin up the 15% grades in the NSW border ranges much more easily than the 11-32 x 24T low ring on the Eclipse; and (iii) I think that the Marathon Supremes I have on the Eclipse will manage the Queensland debris better than the M'thon Racers on the Eclipse.

And on ti bolts, etc.:  stick with quality stainless, Pavel -- use marine grade if need be.

mickeg

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Re: Titanium bolts? Mad waste of money or any purpose?
« Reply #24 on: January 10, 2018, 09:03:03 pm »
Jan Heine has posted a cogent piece on the uses of titanium on bikes, weight savings, and design appropriateness here:
https://janheine.wordpress.com/2018/01/09/myth-2-titanium-is-lighter-than-steel/

Best,

Dan.

Thanks for posting.  Nice brief writeup. 

Regarding his discussion of fitting a crankset, I found that interesting as the right side chainstay on my bike is in part a solid piece of Titanium instead of entirely tubular.  Photo attached, you can see the chainstay aft of the chainrings becomes tubular but in front of that is solid.  I did not have to use a wider bottom bracket, normal crank and bottom bracket fit just fine.

« Last Edit: January 10, 2018, 09:04:49 pm by mickeg »

Andre Jute

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